Prosthetic Valves with Thrombus Anchoring Strips

This application is a continuation of PCT Application No. PCT/US2023/082844, filed Dec. 7, 2023, which claims the benefit of U.S. Provisional Application No. 63/432,734, filed Dec. 15, 2022, the entire contents of each of which are incorporated by reference herein.

The present invention relates to prosthetic valves that include strips disposed internally to the frames of the valves and configured to allow adherence of thrombus or other tissue thereto.

Native heart valves, such as the aortic, pulmonary and mitral valves, function to assure adequate directional flow from, and to, the heart, and between the heart's chambers, to supply blood to the whole cardiovascular system. Various valvular diseases can render the valves ineffective and require replacement with artificial valves. Surgical procedures can be performed to repair or replace a heart valve. Conventional surgically implantable prosthetic valve typically include a leaflet assembly mounted within a relatively rigid support frame or ring. Components of the prosthetic valve are usually assembled with one or more biocompatible fabrics, and a fabric-covered sewing ring is provided around the valve for suturing to the tissue of the native leaflet.

Since surgeries are prone to an abundance of clinical complications, alternative less invasive techniques of delivering a prosthetic heart valve over a catheter and implanting it over the native malfunctioning valve have been developed over the years. Different types of prosthetic heart valves are known to date, including balloon expandable valve, self-expandable valves and mechanically-expandable valves.

Different methods of delivery and implantation are also known, and may vary according to the site of implantation and the type of prosthetic valve. One exemplary technique includes utilization of a delivery assembly for delivering a prosthetic valve in a crimped state, from an incision which can be located at the patient's femoral or iliac artery, toward the native malfunctioning valve. Once the prosthetic valve is properly positioned at the desired site of implantation, it can be expanded against the surrounding anatomy, such as an annulus of a native valve, and the delivery assembly can be retrieved thereafter.

Most expandable prosthetic valve include flexible leaflets attached to expandable frames thereof, wherein the leaflets are configured to transition between closed and open states, so as to regulate flow of blood through the prosthetic valves. In some cases, regions of the prosthetic valve might be subjected to blood stasis, low flow, or recirculation zones between the leaflets and the frame. Stagnant or otherwise disturbed pools of blood behind the leaflets can cause thrombus formations, loosely attached to an inner skirt covering the inner surface of the valve's frame and facing the leaflets. Since most of the conventional inner skirts are thromboresistant, or at least not formed to encourage tissue adherence thereto, such thrombotic deposits may occasionally detach from the skirt and travel downstream, posing a risk of occluding narrower portions of the vasculature.

According to some aspects of the disclosure, there is provided a prosthetic valve comprising a frame, a strip circumferentially disposed about an inner surface of the frame, and a valvular structure coupled to the strip. The frame is movable between a radially compressed state and a radially expanded state. The strip comprises a strip internal surface facing a central axis of the prosthetic valve. The valvular structure comprises a plurality of leaflets extending inward from the strip internal surface.

In some examples, the strip is configured to allow tissue adherence to the strip internal surface.

According to some aspects of the disclosure, there is provided a prosthetic valve comprising a frame, an inner skirt coupled to an inner surface of the frame, a strip coupled to an internal surface of the skirt, and a plurality of leaflets coupled to the strip internal surface. The frame is movable between a radially compressed state and a radially expanded state. The leaflets are configured to regulate flow through the prosthetic valve. The strip comprises a strip internal surface.

In some examples, the inner skirt is configured to allow formation of neointimal tissue that does not exceed an average thickness threshold.

In some examples, the strip is configured to encourage adherence of tissue of any thickness to the strip internal surface.

The aspects of this disclosure can be used in combination or separately. This summary is provided to introduce a selection of concepts in a simplified form that are further described below in the detailed description. This summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter. The foregoing and other objects, features, and advantages of the invention will become more apparent from the following detailed description, which proceeds with reference to the accompanying figures.

For purposes of this description, certain aspects, advantages, and novel features of the examples of this disclosure are described herein. The disclosed methods, apparatus, and systems should not be construed as being limiting in any way. Instead, the present disclosure is directed toward all novel and nonobvious features and aspects of the various disclosed examples, alone and in various combinations and sub-combinations with one another. The methods, apparatus, and systems are not limited to any specific aspect or feature or combination thereof, nor do the disclosed examples require that any one or more specific advantages be present, or problems be solved. The technologies from any example can be combined with the technologies described in any one or more of the other examples. In view of the many possible examples to which the principles of the disclosed technology may be applied, it should be recognized that the illustrated examples are only preferred examples and should not be taken as limiting the scope of the disclosed technology.

Although the operations of some of the disclosed examples are described in a particular, sequential order for convenient presentation, it should be understood that this manner of description encompasses rearrangement, unless a particular ordering is required by specific language set forth below. For example, operations described sequentially may in some cases be rearranged or performed concurrently. Moreover, for the sake of simplicity, the attached figures may not show the various ways in which the disclosed methods can be used in conjunction with other methods. Additionally, the description sometimes uses terms like “provide” or “achieve” to describe the disclosed methods. These terms are high-level abstractions of the actual operations that are performed. The actual operations that correspond to these terms may vary depending on the particular implementation and are readily discernible by one of ordinary skill in the art.

All features described herein are independent of one another and, except where structurally impossible, can be used in combination with any other feature described herein.

As used in this application and in the claims, the singular forms “a,” “an,” and “the” include the plural forms unless the context clearly dictates otherwise. Additionally, the terms “have” or “includes” means “comprises”. Further, the terms “coupled”, “connected”, and “attached”, as used herein, are interchangeable and generally mean physically, mechanically, chemically, magnetically, and/or electrically coupled or linked and does not exclude the presence of intermediate elements between the coupled or associated items absent specific contrary language. As used herein, “and/or” means “and” or “or”, as well as “and” and “or”.

Directions and other relative references may be used to facilitate discussion of the drawings and principles herein, but are not intended to be limiting. For example, certain terms may be used such as “inner,” “outer,” “upper,” “lower,” “inside,” “outside,”, “top,” “bottom,” “interior,” “exterior,” “left,” right,” and the like. Such terms are used, where applicable, to provide some clarity of description when dealing with relative relationships, particularly with respect to the illustrated examples. Such terms are not, however, intended to imply absolute relationships, positions, and/or orientations. For example, with respect to an object, an “upper” part can become a “lower” part simply by turning the object over. Nevertheless, it is still the same part and the object remains the same.

The term “plurality” or “plural” when used together with an element means two or more of the element. Directions and other relative references (e.g., inner and outer, upper and lower, above and below, left and right, and proximal and distal) may be used to facilitate discussion of the drawings and principles herein but are not intended to be limiting.

The terms “proximal” and “distal” are defined relative to the use position of a delivery apparatus. In general, the end of the delivery apparatus closest to the user of the apparatus is the proximal end, and the end of the delivery apparatus farthest from the user (e.g., the end that is inserted into a patient's body) is the distal end. The term “proximal” when used with two spatially separated positions or parts of an object can be understood to mean closer to or oriented towards the proximal end of the delivery apparatus. The term “distal” when used with two spatially separated positions or parts of an object can be understood to mean closer to or oriented towards the distal end of the delivery apparatus. The terms “longitudinal” and “axial” are interchangeable, and refer to an axis extending in the proximal and distal directions, unless otherwise expressly defined.

It should be understood that the disclosed examples can be adapted to deliver inflatable balloons, and in some implementations, to deliver and implant prosthetic devices expandable by such inflatable balloons, to and/or in any of the native annuluses of the heart (e.g., the aortic, pulmonary, mitral, and tricuspid annuluses), and can be used with any of various delivery approaches (e.g., retrograde, antegrade, transseptal, transventricular, transatrial, etc.).

Throughout the figures of the drawings, different superscripts for the same reference numerals are used to denote different examples of the same elements. Examples of the disclosed devices and systems may include any combination of different examples of the same elements. Specifically, any reference to an element without a superscript may refer to any alternative example of the same element denoted with a superscript. In order to avoid unduc clutter from having too many reference numbers and lead lines on a particular drawing, some components will be introduced via one or more drawings and not explicitly identified in every subsequent drawing that contains that component.

show perspective views of an exemplary prosthetic valve, with and without an outer skirtsurrounding the frame, respectively.shows the framewithout any other soft components attached thereto. The term “prosthetic valve”, as used herein, refers to any type of a prosthetic valve deliverable to a patient's target site over a catheter, which is radially expandable and compressible between a radially compressed, or crimped, state, and a radially expanded state. Thus, the prosthetic valve can be crimped on or retained by an implant delivery apparatus (not shown) in the radially compressed state during delivery, and then expanded to the radially expanded state once the prosthetic valve reaches the implantation site. The expanded state may include a range of diameters to which the valve may expand, between the compressed state and a maximal diameter reached at a fully expanded state. Thus, a plurality of partially expanded states may relate to any expansion diameter between radially compressed or crimped state, and maximally expanded state. A prosthetic valve of the current disclosure (e.g., prosthetic valve,) may include any prosthetic valve configured to be mounted within the native aortic valve, the native mitral valve, the native pulmonary valve, and the native tricuspid valve.

It is understood that the prosthetic valves disclosed herein may be used with a variety of implant delivery apparatuses. Balloon expandable valves generally involve a procedure of inflating a balloon within a prosthetic valve, thereby expanding the prosthetic valve within the desired implantation site. Once the valve is sufficiently expanded, the balloon is deflated and retrieved along with a delivery apparatus (not shown). Self-expandable valves include a frame that is shape-set to automatically expand as soon an outer retaining shaft or capsule (not shown) is withdrawn proximally relative to the prosthetic valve. Mechanically expandable valves are a category of prosthetic valves that rely on a mechanical actuation mechanism for expansion. The mechanical actuation mechanism usually includes a plurality of expansion and locking assemblies (such as the prosthetic valves described in U.S. Pat. No. 10,603,165, International Application No. PCT/US2021/052745 and U.S. Provisional Application Nos. 63/085,947 and 63/209,904, each of which is incorporated herein by reference in its entirety), releasably coupled to respective actuation assemblies of a delivery apparatus, controlled via a handle (not shown) for actuating the expansion and locking assemblies to expand the prosthetic valve to a desired diameter. The expansion and locking assemblies may optionally lock the valve's diameter to prevent undesired recompression thereof, and disconnection of the actuation assemblies from the expansion and locking assemblies, to enable retrieval of the delivery apparatus once the prosthetic valve is properly positioned at the desired site of implantation.

show an example of a prosthetic valve, which can be a balloon expandable valve or any other type of valve, illustrated in an expanded state. The prosthetic valvecan comprise an outflow endand an inflow end. In some instances, the outflow endis the proximal end of the prosthetic valve, and the inflow endis the distal end of the prosthetic valve. Alternatively, depending for example on the delivery approach of the valve, the outflow end can be the distal end of the prosthetic valve, and the inflow end can be the distal end of the proximal valve.

The term “outflow”, as used herein, refers to a region of the prosthetic valve through which the blood flows through and out of the prosthetic valve.

The term “inflow”, as used herein, refers to a region of the prosthetic valve through which the blood flows into the prosthetic valve.

In the context of the present application, the terms “lower” and “upper” are used interchangeably with the terms “inflow” and “outflow”, respectively. Thus, for example, the lower end of the prosthetic valve is its inflow end and the upper end of the prosthetic valve is its outflow end.

In the context of the present application, the terms “lower” and “upper” are used interchangeably with the terms “distal to” and “proximal to”, respectively. Thus, for example, a lowermost component can refer to a distal-most component, and an uppermost component can similarly refer to a proximal-most component.

The terms “longitudinal” and “axial”, as used herein, refer to an axis extending in the proximal and distal directions, unless otherwise expressly defined.

The prosthetic valvecomprises an annular framemovable between a radially compressed configuration and a radially expanded configuration, and a valvular structuremounted within the frame. The framecan be made of various suitable materials, including plastically-deformable materials such as, but not limited to, stainless steel, a nickel based alloy (e.g., a cobalt-chromium or a nickel-cobalt-chromium alloy such as MP35N alloy), polymers, or combinations thereof. When constructed of a plastically-deformable materials, the framecan be crimped to a radially compressed state on a balloon catheter, and then expanded inside a patient by an inflatable balloon or equivalent expansion mechanism. Alternatively or additionally, the framecan be made of shape-memory materials such as, but not limited to, nickel titanium alloy (e.g., Nitinol). When constructed of a shape-memory material, the framecan be crimped to a radially compressed state and restrained in the compressed state by insertion into a shaft or equivalent mechanism of a delivery apparatus.

In the example illustrated in-IC, the frameis an annular, stent-like structure comprising a plurality of intersecting struts. In this application, the term “strut” encompasses axial struts, angled struts, laterally extendable struts, commissure windows, commissure support struts, support posts, and any similar structures described by U.S. Pat. Nos. 7,993,394 and 9,393,110, which are incorporated herein by reference. A strutmay be any elongated member or portion of the frame. The framecan include a plurality of strut rungs that can collectively define one or more rows of cells. The framecan have a cylindrical or substantially cylindrical shape having a constant diameter from the inflow endto the outflow endas shown, or the frame can vary in diameter along the height of the frame, as disclosed in U.S. Pat. No. 9,155,619, which is incorporated herein by reference.

The end portions of the strutsare forming apicesat the outflow endand apicesat the inflow end. The strutscan intersect at additional junctionsformed between the outflow apicesand the inflow apices. The junctionscan be equally or unequally spaced apart from each other, and/or from the apices,, between the outflow endand the inflow end.

The strutscan include a plurality of angled struts and vertical or axial struts.show an exemplary prosthetic valvethat can be representative of, but is not limited to, a balloon expandable prosthetic valve. The frameof the prosthetic valveillustrated incomprises rungs of angled struts and axial struts disposed between some of the rungs of the angled struts. In such implementations of the frame, the struts can be pivotable or bendable relative to each other, so as to permit frame expansion or compression. For example, the framecan be formed from a single piece of material, such as a metal tube, via various processes such as, but not limited to, laser cutting, electroforming, and/or physical vapor deposition, while retaining the ability to collapse/expand radially in the absence of hinges and like.

A valvular structure, shown also for example in, can include a plurality of leaflets(e.g., three leaflets), positioned at least partially within the frame, and configured to regulate flow of blood through the prosthetic valvefrom the inflow endto the outflow end. While three leafletsarranged to collapse in a tricuspid arrangement, are shown in the example illustrated in, it will be clear that a prosthetic valvecan include any other number of leaflets. Adjacent leafletscan be arranged together to form commissuresthat are coupled (directly or indirectly) to respective portions of the frame, thereby securing at least a portion of the valvular structureto the frame. The leafletscan be made from, in whole or part, biological material (e.g., pericardium), bio-compatible synthetic materials, or other such materials. Further details regarding transcatheter prosthetic valves, including the manner in which the valvular structurescan be coupled to the frameof the prosthetic valve, can be found, for example, in U.S. Pat. Nos. 6,730,118, 7,393,360, 7,510,575, 7,993,394, 8,652,202, and 11,135,056, all of which are incorporated herein by reference in their entireties.

As shown for example in, three separate leafletscan collectively define the valvular structurein some cases. Each leafletcan have a rounded cusp edgeopposite a free edge, and a pair of generally oppositely-directed tabsseparating the cusp edgeand the free edge. The cusp edgein such cases forms a single scallop. Each leafletfurther comprises an inner surface (not annotated), defined as the surface facing the valve central axis Ca (indicated in), and an outer surface (not annotated), opposite thereto so as to face the frame.

When such leafletsare coupled to the frame and to each other, the lower edge of the resulting valvular structuredesirably has an undulating, curved scalloped shape. By forming the leaflets with this scalloped geometry, stresses on the leafletsare reduced which, in turn, improves durability of the prosthetic valve. Moreover, by virtue of the scalloped shape, folds and ripples at the belly of each leaflet, which can cause early calcification in those areas, can be eliminated or at least minimized. The scalloped geometry also reduces the amount of tissue material used to form the valvular structure, thereby allowing a smaller, more even crimped profile at the inflow end of the valve.

The leafletsdefine a non-planar coaptation plane (not annotated) when their free edgesco-apt with each other to seal blood flow through the prosthetic valve. Leafletscan be secured to one another at their tabsto form commissuresof the valvular structure, which can be secured, directly or indirectly, to structural elements connected to the frameor integrally formed as portions thereof, such as commissure posts, commissure windows, and the like. When secured to two other leafletsto form valvular structure, the cusp edgesof the leafletscollectively form the scalloped lineof the valvular structure. Each leafletcomprises a leaflet body, defined between the line of attachment of the leaflet to the frame, for example along scalloped line, and the free edge. The leaflet bodydefines the movable portion of the leaflet, free to move toward the framein an open state of the valvular structure, and toward central axis Ca to co-apt with other leafletsin a closed state of the valvular structure. The lowest or distal-most end of each leafletis at cusp edge midpoint, which in turn also defines the lowest or distal-most region of scalloped line.

In some examples, the prosthetic valvecan comprise at least one skirt or scaling member.show an example of a prosthetic valvethat includes an inner skirt, which can be secured to the inner surface(annotated, for example, in) of the frame. Such an inner skirtcan be configured to function, for example, as a scaling member to prevent or decrease perivalvular leakage. An inner skirtcan further function as an anchoring region for valvular structureto the frame, and/or function to protect the leafletsagainst damage which may be caused by contact with the frame, for example during valve crimping or during working cycles of the prosthetic valve.shows an inner skirtdisposed around and attached to the inner surfaceof frame, wherein the valvular structureis sutured to the inner skirtalong scalloped line. The inner skirtcan be coupled to the framevia sutures or another form of coupler.

The prosthetic valvecan comprise, in some examples, an outer skirtmounted on the outer surface(annotated, for example, in) of frame, configure to function, for example, as a sealing member retained between the frameand the surrounding tissue of the native annulus against which the prosthetic valve is mounted, thereby reducing risk of paravalvular leakage (PVL) past the prosthetic valve. The outer skirtcan be coupled to the framevia sutures or another form of coupler.

Any of the inner skirtand/or outer skirtcan be made of various suitable biocompatible materials, such as, but not limited to, various synthetic materials (e.g., PET) or natural tissue (e.g. pericardial tissue). In some cases, the inner skirtcan be formed of a single sheet of material that extends continuously around the inner surfaceof frame. In some cases, the outer skirtcan be formed of a single sheet of material that extends continuously around the outer surfaceof frame.

The outer skirtcan define an internal surface (not annotated) facing and optionally contacting the outer surfaceof the frame, and an opposite external surfacefacing away from the frame, toward the surrounding anatomy when implanted in a patient's body. In some examples, as illustrated for example in a cross-sectional view of prosthetic valvein, the outer skirt can include an outer portionextending over at least a portion of the outer surfaceof frame, and fold over the framealong the inflow endto further include an inner portionextending over a portion of the inner surfaceof frame, extending over a limited height between the inflow endand the inner skirt, for example. In such cases, the external surfaceof the outer skirtcan be defined only over the outer portion, and not the inner portion. Such configurations, in which the outer skirtcovers inflow apices, can advantageously provide an atraumatic inflow endof the prosthetic valve, preventing the inflow apicesfrom accidentally engaging or snagging portions of the delivery apparatusduring advancement through the patient's vasculature to the site of implantation.

While an outer skirtis illustrated throughout some of the drawings of the current specification, such as, to fold over inflow apicesso as to include both an inner portionand an outer portion, it is to be understood that this configuration is shown by way of illustration and not limitation, and that an outer skirtcan similarly extend only over the outer surfaceof the frame, such that it includes the outer portionand does not necessarily define an inner portion.

In some implementations, the inner skirtis configured to be relatively thromboresistant. For example, the inner skirtcan include at least one or more of a polytetrafluorocthylene (PTFE), an ultra-high molecular weight polyethlene (UHMWPE), or a coated thermoplastic polyurethane (TPU). The polytetrafluoroethylene (PTFE) may comprise expanded polytetrafluorocthylene (cPTFE) in some examples as desired. Various other thromboresistant materials may be utilized as desired. In some examples, a thromboresistant coating may be utilized with the inner skirt. For example, a coating of PTFE or ePTFE may be applied to material of the inner skirt, which may comprise polyethylene terephthalate (PET) or another form of material. The underlying material of the inner skirtin such examples, may be a material that allows for tissue ingrowth, such as PET, yet is coated with a thromboresistant coating. In some examples, the material of the inner skirtmay be fabricated to be thromboresistant. For example, a knit pattern of the material of the inner skirtmay be configured to be thromboresistant, with micropatterns or other forms of knit patterns. A knit PTFE fabric may be utilized in some examples. The material of the inner skirtcan include a smooth texture to be thromboresistant and inhibit tissue growth. Combinations of such features may be utilized to result in a thromboresistant inner skirt.

In some examples, the outer skirtis configured to allow tissue ingrowth, at least along outer portion. In some examples, the outer skirtcan include polyethylene terephthalate (PET) or another form of material that is configured to allow tissue ingrowth. In some examples, a coating may be utilized with the outer skirtthat is configured to allow tissue ingrowth. For example, a porous coating or other form of coating may be applied to a thromboresistant material such as ultra-high molecular weight polyethlene (UHMWPE) to allow for tissue ingrowth. The underlying material of the outer skirtin such examples, may be a material that inhibits tissue ingrowth, yet is coated with a coating that allows tissue ingrowth, at least over outer portion. In some examples, the material of the outer skirtmay be fabricated to allow tissue ingrowth. For example, a knit pattern of the material of the outer skirtmay be configured to allow tissue ingrowth, with a large knit pattern or other forms of knit patterns. A knit PET fabric may be utilized in some examples. In some examples, the outer skirtmay include yarns (e.g., textured yarns) extending radially outward. The material of the outer skirtmay include a porous texture to allow for tissue ingrowth. Combinations of such features may be utilized to result in an outer skirtthat allows for tissue ingrowth. It is to be understood that for implementations of outer skirtsthat include both an inner portionand an outer portion, any of the examples described hereinabove with respect to encouraging tissue ingrowth may be applied to the outer portion, while the inner portionmay or may not be configured to encourage tissue ingrowth.

illustrate a delivery apparatus, according to an exemplary configuration, adapted to deliver a balloon expandable prosthetic valvedescribed herein (e.g., prosthetic valveor). It should be understood that the delivery apparatuscan be used to implant prosthetic devices other than prosthetic valves, such as stents or grafts.

The delivery apparatusincludes a handleand a balloon catheterhaving an inflatable balloonmounted on its distal end. The prosthetic valvecan be carried in a crimped state over the balloon catheter. Optionally, an outer delivery shaftcan concentrically extend over the balloon catheter, and a push shaftcan be disposed over the balloon catheter, optionally between the balloon catheterand the outer delivery shaft.

The outer delivery shaft, the push shaft, and the balloon catheter, can be configured to be axially movable relative to each other. For example, a proximally oriented movement of the outer delivery shaftrelative to the balloon catheter, or a distally oriented movement of the balloon catheterrelative to the outer delivery shaft, can expose the prosthetic valvefrom the outer delivery shaft. The delivery apparatuscan further include a noseconecarried by a nosecone shaft (hidden from view in) extending through a lumen of the balloon catheter.

The proximal ends of the balloon catheter, the outer delivery shaft, the push shaft, and optionally the nosecone shaft, can be coupled to the handle. During delivery of the prosthetic valve, the handlecan be maneuvered by an operator (e.g., a clinician or a surgeon) to axially advance or retract components of the delivery apparatus, such as the nosecone shaft, the balloon catheter, the outer delivery shaft, and/or the push shaft, through the patient's vasculature, as well as to inflate the balloonmounted on the balloon catheter, so as to expand the prosthetic valve, and to deflate the balloonand retract the delivery apparatusonce the prosthetic valveis mounted in the implantation site.

The handlecan include a steering mechanism configured to adjust the curvature of the distal end portion of the delivery apparatus. In the illustrated example, the handleincludes an adjustment member, such as the illustrated rotatable knob, which in turn is operatively coupled to the proximal end portion of a pull wire. The pull wire can extend distally from the handlethrough the outer delivery shaftand has a distal end portion affixed to the outer delivery shaftat or near the distal end of the outer delivery shaft. Rotating the knobcan increase or decrease the tension in the pull wire, thereby adjusting the curvature of the distal end portion of the delivery apparatus. Further details on steering or flex mechanisms for the delivery apparatus can be found in U.S. Pat. No. 9,339,384, which is incorporated by reference herein. The handlecan further include an adjustment mechanism including an adjustment member, such as the illustrated rotatable knob. The adjustment mechanism can be configured to adjust the axial position of the push shaftrelative to the balloon catheter.

The prosthetic valvecan be carried by the delivery apparatusduring delivery in a crimped state, and expanded by balloon inflation to secure it in a native heart valve annulus. In an exemplary implantation procedure, the prosthetic valveis initially crimped over the balloon catheter, proximal to the inflatable balloon. Because prosthetic valveis crimped at a location different from the location of balloon, prosthetic valvecan be crimped to a lower profile than would be possible if it was crimped on top of balloon. This lower profile permits the clinician to more easily navigate the delivery apparatus(including crimped prosthetic valve) through a patient's vasculature to the treatment location. The lower profile of the crimped prosthetic valve is particularly helpful when navigating through portions of the patient's vasculature which are particularly narrow, such as the iliac artery.